1. Field of the Invention
The present invention is broadly concerned with incubators conventionally used for the incubation of cell-culture samples and which are improved by provision of an internal, continuous sterilization feature. More particularly, the invention pertains to such incubators equipped with internal ultraviolet (UV) lamps which can be user-controlled controlled to effect continuous or periodic sterilization of the internal working chambers of the incubators.
2. Description of the Prior Art
Cell culture incubators are ubiquitous in biological research laboratories. These units are designed to incubate cell culture samples, typically over a period of hours with closely controlled temperature and atmospheric conditions (e.g., 37.degree. C. and 5% CO.sub.2). Typically, incubators are in the form of an upright cabinet having an openable door and an internal working or incubating chamber equipped with a series of sample-holding shelves. Modern-day incubators normally have temperature and CO.sub.2 sensors for maintaining desired internal conditions without operator intervention.
During the course of incubations, the internal working chambers of incubators can become contaminated with air borne or liquid contaminants. As a consequence, it is necessary to sterilize and decontaminate the internal working chamber and components of the incubators. Presently, such sterilization/decontamination is performed by one of two methods. In one technique, all removable components are autoclaved and non-removable components are manually wiped down with a germicidal solution. In another method, the incubator undergoes a sterilization cycle which heats the internal working chamber and its components to approximately 90.degree. C. to kill any contaminants. Both of these prior methods are cumbersome and time-consuming. Manual decontamination requires significant labor, whereas a incubator sterilization cycle disrupts the incubator's operating temperature for several hours both during heating and the subsequent cool down period.
There is accordingly a need in the art for an improved cell culture incubator which avoids the sterilization/decontamination problems described above, and which allows continuous or intermittent sterilization/decontamination without upsetting the desired incubation conditions maintained within the working chamber of the incubator.